Improvement in steam-jets for steam-generator furnaces



UNITED STATES PATENT OFFICE;

DAvID M. NICHOLS, or NEW YonKfN. Y.

IMPROVEMENT IN STEAM-JETS FOR STEAM-GENERATOR FURNACES.

Specification forming part of Letters Patent No. 59,055, dated October 23,1866.

To all whom it may concern:

Be it known that I, DAVID M. NICHOLS, of the city, county, and State of New York, have invented a new and useful Improvement in Steam-Jets; and l do hereby declare that the following is a full, clear, and exact description thereof, which will enable others skilled in the art to make and use the` same, reference being had to the accompanying drawings, forming part of this specification, in which- Figure l represents a transverse vertical section of this invention, the line :r x, Fig. 2, indicating the plane of section. Fig. -2 is a plan or top view of thesame. Fig. 3 is a diagram representing the effect of my jet as compared with the ordinary jets of round nozzles.

Similar letters of reference indicate like parts.

The invention which constitutes the subjectmatter of this patent has reference to the steamjet used for accelerating the current ot' air in flue for steam-boilers and for other purposes. Such jets have heretofore been composed either of a single nozzle or of a series of nozzles arranged parallel to each other in the fine, and all pointing in the same direction 5 but their operation has not been as efficient as the quantity of steam expended would lead one to believe it should be.

As it is always desirable that the natural draft of a flue or chimney should be avail'- able for the purpose ofl lighting the fire, and of maintaining it when great activity of combustion is not required, it has been customaryT -to arrange the nozzles of such jets in the ordinary flue or chimney used to excite the combustion of the fuel for a steam-boiler by natural draft, and as the current of air moving in such a flue by mere draft is necessarily slow, the area of the chimney is proportionately large. On the other hand, the current of air impelled forward by a steam-jet is necessarily rapid; hence the area of the iiue in which it moves should be materially smaller than that used for natural draft, and consequently, if the steam-jet be applied (as has heretofore been the case) to the latter, either a much larger number of nozzles and much larger amount of steam must be used than is necessary for draft alone, so as to keep the entire mass of air in the flue moving in one direction, or, if a less number of nozzles be used than is required for this purpose, they must be set so far apart that reverse currents or eddies will form between the direct currents in the vicinity of the jets of steam, and a portion of the steam will be expended in keeping such eddies in motion, and uselessly as respects the excitement of the draft of air through the fuel.

Myinven tion is designed to obviate the loss of useful effect due to the arrangement of a steamjet in a iue of suitable size for natural draft, and at the same time to enable such a flue to be retained, so that the natural draft may be used in starting the lire, orat other times, as found convenient, and yet the steam-jet can be used when required with the best effect.

To these ends my invention consists of the combination ot' a steam-jet composed of one or more nozzles with a flue divided into two divisions-one of the proper area for the rapid current of air produced by the steam-jet and the other of larger areaand with a valve or valves, by means of which the larger division may be closed or opened. Hence the entire area of the flue may be used (by opening the valve) for the natural draft, or by closing the valve the area in the vicinity ofthe steami jet may be reduced to the proper dimensions to enable the jet of steam to operate to the best effect upon the air, the nozzles, when more than one is used, being set so close together that their effect is concentrated upon the air in the flue, and that the formation of eddies between the direct currents is prevented.

The accompanying drawings represents a steam-jet constructed in accordance with my' invention. In this example a flue, A, i's used of sufficient size to be employed in lighting the fire with the natural draft, and this flue is divided into two divisions by the small pipe B, secured centrally within it. The area of this small pipe is of the proper size for the passage of the current of the gaseous products of combustion when impelled at the requisite speed by the jets of steam. p

The series of nozzles C composing the steamjets are arranged, as seen in the drawing, so

as to act upon the current of gaseous products passing through the small pipe which forms the smaller division of the iiue.

The flue is fitted with two flap-valves, D, which may be opened or closed. When they are opened the whole area of the llue, with the ,exception of that occupied b y the steam-jet, is

available for natural draft.4 When they are closed the area of only the smaller division is left free. Consequently the action of the jets of steam issuing from the nozzles may be concentrated upon `the gaseousiproducts with the best effect, the nozzles may be set so close together that there is no space for the formation of reverse currents between the jets, and the number of nozzles employed, and consequently the quantity of steam expended, may be reduced to the lowest practical limit, although the same apparatus has Within it the-capacity, when the steamA is shut off and the valves opened, toWork with as good e'ect as old apparatuses by the natural draft.

The nozzles of the steam-jet are formed in the present example with square orifices, so that t-he jets issuing from them, if expanded Without change of form, would touch simultaneously at all sides, as indicated in diagram 3, instead of leaving spaces, as circular jets would.

Although I prefer to use a series of nozzles of square or other polygonal section, yet one or more nozzles of the customary form may be used With the divided flue and valves, if deemed expedient.

I have found by experiment that lthe effect appears to be greatest when each nozzle is from one-fourteenth to one-twelfth of an inch square, and when they are arranged so that their centers are from one and one-eighth-inoh to one and one-quarter inch apart; but these measurements may, of course, be varied as found expedient.

I have described steam as the impelling-uid to be used in the nozzles; but it is obvious that air or any gaseous material under pressure may be substituted for steam. In place of forming the divided ilue in the manner thus far described, the sm allpipe which forms the smaller division may be placed outside ot the larger pipe, and may have a separate funnel to discharge through, the valve or valves being applied, as before, to the larger division or funnel.

What I claim as new, and desire to secure by Letters Patent, is

The combination of the steam-jet with a divided lue and a valve for one division of the due, all operating substantially as set forth.

DAVID M. NICHOLS.

Witnesses:

- W in. F. MCNAMARA,

W. HAUFF. 

